TWI386467B - A coating composition, a laminate and a preparation process of the laminate - Google Patents

Description

Coating composition, layer and method for preparing the layer

The present invention relates to a coating composition comprising an aqueous PU, a bridging agent and an adhesion promoter, wherein the aqueous polyurethane (hereinafter referred to as PU) is composed of a fluoride, a diisocyanate, and a polyester or a polyether. Obtained by reaction of an alcohol or a glycol. Since the coating composition of the present invention has good adhesion to a substrate, and particularly has excellent adhesion to a fluorine-containing substrate having a low surface energy, it can be used as an adhesive, and is particularly suitable for use in the textile industry. Further, the present invention further discloses a layer containing a fluorine-containing substrate layer coated with the coating composition and a method of preparing the layer.

In recent years, with the improvement of living standards, consumers' demand and requirements for textiles have also become higher and higher. Therefore, in order to meet the needs of consumers, innovative textile research directions are toward versatility. For example, as a textile for medical protective clothing, it must have both water resistance, breathability, antiviral, comfort and washability to meet the needs of users in this field. To achieve such high requirements, these textiles are usually made up of a plurality of substrates having different functions and materials, such as polytetrafluoroethylene (PTFE) film, PU film, cotton and enamel. Wait. However, since the physical properties of the respective substrates are different, it is a great problem to firmly bond the substrates of different properties. Generally, there are two improved methods, one is to directly modify the adhesive surface of the substrate in order to meet the adhesive requirements of the commonly used adhesive; the other is to develop a novel adhesive suitable for the pre-bonded substrate.

U.S. Patent No. 5,626,950 discloses a moisture permeable waterproof fabric wherein the waterproof fabric comprises a woven fabric and a resin is applied to at least one side of the woven fabric, and the resin is a fluorine-containing coating for the purpose of coating the resin. It is a function to breathe moisture.

US Patent No. 4,433,026 discloses a cloth-like material for a surgical gown and/or a surgical covering cloth, characterized in that the cloth-like material is a layer having three layers, wherein the layer is The product has the characteristics of water repellency, water repellency, air absorbing property and comfort. However, this invention does not further disclose the bonding between layers.

US Patent No. 5,599,610 discloses a washable sterilizable article for hospital and/or medical garments, the article comprising three layers, wherein the intermediate layer is a microporous PU film, the intermediate layer being a polyether- The polyurethane adhesive is applied to the other layers. However, the invention did not perform more high temperature water wash tests, but only performed 50 times. Therefore, it is not possible to confirm whether the object retains the structural integrity after more tests.

Therefore, in order to achieve the demand and high requirements for versatile materials (for example, woven or non-woven) in different application fields (especially medical fabrics or close-fitting fabrics), materials with different physical or chemical properties can be stabilized. The adhesive of the ground bond plays an important role in this, because the application of an appropriate adhesive can increase the convenience of the bonding process, the adhesion at the time of bonding, the water wash resistance after bonding, the high temperature resistance, Durability and more.

In view of the above, the present invention is directed to providing a coating composition having superior adhesion properties, which comprises 0.001 to 99.998% by weight of aqueous PU; 0.001 to 10% by weight of a bridging agent; and 0.001 to 5% by weight of a tackifier; Among them, the aqueous PU is obtained by reacting a fluoride, a diisocyanate, and a polyol of a polyester or a polyether.

One object of the present invention is to provide the use of the coating composition of the present invention as an adhesive.

Further, another object of the present invention is to provide a layered material comprising a fluorine-containing substrate layer coated with the coating composition of the present invention. The layered material of the present invention is characterized in that the fluorine atom contained in the coating composition of the present invention can form a strong adsorption force with the fluorine atom on the surface of the fluorine-containing substrate (that is, the principle of homology compatibility), and the coating composition The material not only has excellent adhesion to general fluorine-containing substrates, but also has good adhesion to PTFE films which are low in surface energy (18.5 dyne/cm) and difficult to adhere.

In addition, the use of the coating composition of the present invention as an adhesive can not only reduce the time and cost of modifying the surface to be bonded of the substrate, but also increase the convenience of attaching the commercially available PTFE film and the adhesion. Washability of the layer of the PTFE film. The layer also has the gas permeability and water repellency inherent in the PTFE film itself, thus making the layer of the present invention suitable for a variety of applications.

Further, the present invention has an object to further provide a method of producing a layer containing the coating composition of the present invention.

The coating composition of the present invention comprises from 0.001 to 99.998% by weight of aqueous PU, preferably from about 50.0 to about 99.0% by weight, particularly preferably from about 90 to about 99.0% by weight; from 0.001 to 10% by weight of bridging agent, preferably From about 2 to about 7 wt%, particularly preferably from about 3 to about 5 wt%; and from 0.001 to 5 wt% of a tackifier, preferably from about 1 to about 5 wt%, particularly preferably from about 2 to about 4 wt%, wherein the bridge The agent system includes a bridging agent containing an NCO functional group and the tackifier comprises an aqueous nonionic tackifier. Further, the coating composition of the present invention has a viscosity of from 4,000 to 10,000 cp, preferably from about 5,000 to about 8,000 cp, particularly preferably from about 5,000 to about 6,000 cp. In addition, the coating composition of the present invention may also be added with additional additives as needed to increase performance in different fields of application.

The aqueous PU in the coating composition of the present invention is obtained by reacting a fluoride, a diisocyanate, and a polyol of a polyester or a polyether, and the fluoride used is a fluorine which is common in the technical field of the present invention and is easily commercially available. a compound (for example, the following formula), and preferably a fluorine-containing glycol, particularly preferably 4,4'-(hexafluoroisopropylidene)diphenol; the diisocyanate used is a technical field of the invention a conventional diisocyanate (for example: 1,4-butylene diisocyanate, 1,6-exexyl diisocyanate, 1,12-exadecyl diisocyanate, cyclohexane-1,3- or 1,4-Diisocyanate, isophorone diisocyanate (IPDI), 1,3- or 1,4-α,α,α',α',-tetramethylbenzenedimethyl diisocyanate, 2,4 - or 2,6-diisocyanatotoluene, 2,2'-, 2,4'- or 4,4'-diisocyanatodiphenylmethane (MDI), 1,5-naphthalene diisocyanate , p- or m-phenylene diisocyanate, phenyldimethyl diisocyanate and diphenyl-4,4'-diisocyanate, and hexamethyldiisocyanate (HDI), etc., and preferably hexamethyl Diisocyanate (HDI); and the polyester or poly used The polyol is a polyester or polyether polyol which is well known in the art and is commercially available, preferably polytetramethylene ether glycol (PTMEG) and polybutylene adipate. (PBA). Further, in the preparation of the fluorine-containing aqueous PU, the chain extender used is a chain extender which is conventionally available in the technical field of the invention and is easily commercially available, and is preferably a hydrazine (HZ) or a diethanolamine ( DEA) and 1,3-propane sultone.

Further, the above aqueous PU can be obtained by the following steps:

1. The fluoride is dissolved in a solvent, and the solvent is a suitable solvent which is well known in the art and is readily available commercially, preferably 1-methyl-2-pyrrolidone (NMP).

2. Mixing the polyester and/or polyether polyol with the fluoride containing solution, and heating to 80 ° C ~ 100 ° C, uniformly mixed for 5 ~ 30min;

3. Adding diisocyanate to the solution, and stirring at 80-300 rpm at 80 ° C to 100 ° C, using a titration method to determine the end point of the reaction to determine the prepolymerization time;

4. After cooling the solution, add acetone;

5. adding a diamine chain extender to the solution, and stirring at 50 ° C to 60 ° C for 20 to 50 minutes, adding water and stirring;

6. After removing the acetone in the solution, a fluorine-containing aqueous PU can be obtained.

In the above method for preparing an aqueous PU, the amount of the fluoride, polyester and/or polyether polyol, diisocyanate and diamine chain extender may be selected by a person having ordinary knowledge in the art as the case may be. .

Further, the present invention provides a layer comprising the coating composition of the present invention, which further comprises one or more material layers, wherein the material layer is polyester, polypropylene (PP), polytetrafluoroethylene (PTFE), polyethylene (PE), polyethylene terephthalate (PET), polyurethane (PU), cotton and tantalum (preferably PTFE), and optionally free The group it consists of. Further, the above material layers are different forms of fabric (for example: knitted and woven or tricot, etc.) and non-woven (for example, non-woven). In addition to this, the material layer can also be a microporous or non-porous film.

In a specific embodiment of the present invention, the layer comprises a PET tricot layer, a PTFE layer, and a PET cloth layer, wherein the PTFE is coated with the coating composition of the present invention and attached to a PET mesh (PET tricot). Layer or PET layer, as shown in Figure 1.

The invention also provides a method of making a layer comprising the following steps:

(1) coating the coating composition of the present invention on the first substrate;

(2) pre-drying the first substrate;

(3) laminating the surface of the first substrate coated with the coating composition of the present invention with a fluorine-containing substrate to form a layer;

(4) heating the layer and then cooling;

(5) applying the coating composition of the present invention to the fluorine-containing substrate in the layer;

(6) pre-drying the layer;

(7) laminating the fluorine-containing substrate of the layer with the second substrate;

(8) heating the layer with the first and second substrates and then cooling.

The material of the first or second substrate in the above steps is, for example, polyester, polypropylene (PP), polytetrafluoroethylene (PTFE), polyethylene (PE), polyethylene terephthalate ( Conventional materials (preferably polyester, PP, PTFE, PE or PET) of PET), polyurethane, PU and ruthenium, and the materials of the fluorine-containing substrate are also used for this technology. A material well known in the art, and preferably PTFE. In addition, these materials may be microporous or non-porous films in addition to fabrics (e.g., knitted, plain woven or tricot) and non-woven forms. In a specific embodiment, the first or second substrate is a PET fabric and PET tricot, and the fluorine-containing substrate is PTFE.

In the process of producing the layer of the present invention, the first or second substrate may optionally be pretreated with a water repellent agent so that the coating composition of the present invention can be uniformly applied to the surface without causing the coating. The problem of the cloth composition being through the first or second substrate. The water repellent may be a conventional water repellent, preferably a fluorine-containing water repellent. The so-called water repellent pretreatment is to attach the water repellent to the substrate by a general post-treatment method (for example, pressure suction or dipping). In a specific embodiment of the present invention, the water repellent pretreatment of the first or second substrate is about 0.1 to about 0.5%, preferably about 0.2 to about 0.4% by weight of the water repellent is treated by a normal temperature. The film was attached to the substrate, followed by drying at 80 ° C for 1 min, and finally at 160 ° C for 2 min. In the above embodiments, the water repellent used is a water repellent which is optionally commercially available to those of ordinary skill in the art.

In order to complete the layered product of the present invention, the coating composition in the step (1) or (5) has a coating thickness of 0.01 to 0.05 mm, preferably 0.01 to 0.03 mm. In the two steps, the method of applying the coating composition may be a conventional coating method, and is preferably blade coating and spot coating. Further, the pre-drying temperatures of the steps (2) and (6) are 70 to 90 ° C, preferably 70 to 80 ° C; and the heating conditions of the steps (4) and (8) are 100 to 140 ° C (preferably). It is heated at 100 to 130 ° C for 0.5 to 3 minutes (preferably 1 to 3 minutes). For the heat treatment in the steps (4) and (8), the purpose is to perform a thermal bridging action between the coating composition as an adhesive and the substrate, so that the adhesive is on the surface of the rough substrate (for example The surface of the microporous PTFE film is cured to further increase the adhesion between the adhesive and the surface of the substrate.

The following are examples of the invention wherein Examples A(a) through (c) are preparations of aqueous PUs having different amounts of fluorine (as shown in Table 1):

A. Synthesis of aqueous polyurethane (waterborne PU)

(a) Preparation of Formulation A

1. 150 g of polytetramethylene ether glycol 2000 (PTMEG 2000) and 150 g of polybutylene adipate (PBA 2000) were used to remove water.

2. 35.28 g of hexamethyl diisocyanate (HDI) was added to the solution and stirred at 150 rpm for 200 min at 90 °C.

3. The solution was taken out of the oil bath and cooled at room temperature.

4. Slowly add 210 ml of acetone.

5. Mix 1.68 g of hydrazine (HZ), 1.40 g of diethanolamine (DEA) and 14.34 g of 1,3-propane sultone (ES 200L), add to the solution, and stir at 55 ° C. 30min.

6. Add 352.7 ml of water and stir.

7. Remove the acetone from the solution.

8. A fluorine-containing aqueous PU can be obtained.

(b) Preparation of Formulation B

1. 5.04 g of 4,4'-(hexafluoroisopropylidene)diphenol (CB) and 10 g of 1-methyl-2-pyrrolidone (NMP) were stirred and dissolved together.

2. 135 g of polytetramethylene ether glycol 2000 (PTMEG 2000) and 135 g of polybutylene adipate (PBA 2000) were used to remove water.

3. Mix the products obtained in steps (1) and (2) and heat the resulting solution to about 90 ° C and stir for 10 min.

4. 35.28 g of hexamethyl diisocyanate (HDI) was added to the solution and stirred at 150 rpm for 200 min at 90 °C.

5. The solution was taken out of the oil bath and cooled at room temperature.

6. Slowly add 189 ml of acetone.

7. Mix 1.68 g of hydrazine (HZ), 1.4 g of diethanolamine (DEA) and 14.34 g of 1,3-propane sultone (ES 200L), add to the solution, and stir at 55 ° C. 30min.

8. Add 317.74 ml of water and stir.

9. Remove the acetone from the solution.

10. A fluorine-containing aqueous PU (a solid content of about 50% and a total amount of about 650 ml) can be obtained.

(c) Preparation of Formulation C

1. 10.08 g of 4,4'-(hexafluoroisopropylidene)diphenol (CB) and 20 g of 1-methyl-2-pyrrolidone (NMP) were stirred and dissolved together.

2. 120 g of polytetramethylene ether glycol 2000 (PTMEG 2000) and 1120 g of polybutylene adipate (PBA 2000) were used to remove water.

3. Mix the products obtained in steps (1) and (2) and heat the resulting solution to about 90 ° C and stir for 10 min.

4. 35.28 g of hexamethyl diisocyanate (HDI) was added to the solution and stirred at 150 rpm for 200 min at 90 °C.

5. The solution was taken out of the oil bath and cooled at room temperature.

6. Slowly add 168 ml of acetone.

7. Mix 1.68 g of hydrazine (HZ), 1.40 g of diethanolamine (DEA) and 14.34 g of 1,3-propane sultone (ES 200 L), add to the solution, and stir at 55 ° C. 30min.

8. Add 282.78 ml of water and stir.

9. Remove the acetone from the solution.

10. A fluorine-containing aqueous PU can be obtained.

B. Preparation of a layer containing a PTFE film

1. A 0.1 to 0.5 wt% water repellent (Unidyne TG823, Biotech Co., Ltd.) was subjected to a pressure suction treatment on a PET fabric, followed by drying at 80 ° C for 1 min and then heat treatment at 160 ° C for 2 min.

2. The present invention contains 95% by weight of aqueous PU, 4% by weight of bridging agent (Wt-2102, Anfeng Chemical) and 1% of tackifier (1010, Tongyu Industrial) by knife coating or spot coating. The adhesive (viscosity from about 5,000 to about 6000 cp) was applied to a water repellent treated PET fabric (coating thickness of about 0.02 mm).

3. After pre-drying the PET fabric with the adhesive coating at 70 ° C, the PTFE film was bonded to the adhesive surface of the PET fabric to obtain a layer of a PET fabric/PTFE film.

4. The layer was heat treated at 120 ° C for 2 min and then cooled to room temperature.

5. The above-mentioned adhesive of the present invention is applied to the PTFE film surface of the layer by a doctor blade coating or a spot coating method (coating thickness is about 0.02 mm).

6. After pre-drying the layer at 70 ° C, the PTFE film side of the layer was bonded to PET tricot to obtain a layer of PET fabric / PTFE film / PET tricot.

7. The layer was heat treated at 120 ° C for 2 min and then cooled to room temperature.

C. Washability and high temperature resistance test of layer containing PTFE film

1. The sample to be tested was placed in a sterile axe at 132 ° C for 10 min.

2. Washing and drying according to AATCC135 standard.

3. After observing the appearance of the sample, tear it away and observe its appearance.

D. Adhesion performance test of different fluorine-containing coating compositions

First, an aqueous PU was prepared by the synthesis steps as in Examples A(a) to (c), wherein the proportion of fluorine added was 0 wt%, 0.26 wt%, and 0.56 wt% (based on the total amount of aqueous PU), and then In the step of Example B, these aqueous PUs having different fluorine ratios were prepared into a coating composition and a layer containing a PTFE film (referred to as a PTFE film in Table 2) at the same time, and finally the layer was exemplified. C high temperature and water wash resistance test and peel strength test, the test results are shown in Table 2.

In Table 2, "high temperature water washing" refers to the high temperature treatment and water washing treatment of Example C; the appearance of "good" means that the appearance of the test sample does not change; the appearance "peeling" refers to the peeling phenomenon and peeling of the test sample. In the strength, "PTFE membrane breakage" refers to a PTFE membrane layer having a plurality of layers, and the layers and layers inside the multilayer PTFE material are peeled off, and are not peeled off in the resin layer, that is, "material break" indicates that the strength is measured. The falling layer is PTFE and also indicates that the strength of the resin is good.

It can be found from Table 2 that in the layer of 9 water washing and high-temperature treatment, the test sample of the fluorine-free adhesive has a material peeling appearance, and an adhesive containing 0.26 wt% and 0.56 wt% of fluorine. The test sample showed no peeling appearance; in the 21 times of water washing and high temperature treatment, the test sample containing 0.26 wt% of fluorine was found to have a material peeling appearance and 0.56 wt% of fluorine. The test sample of the adhesive showed no peeling appearance; and in the layer of 75 water washing and high-temperature treatment, the test sample containing the adhesive of 0.56 wt% of fluorine showed peeling of the appearance. Therefore, it can be understood that as the fluorine content of the adhesive is higher, the adhesion to the PTFE film is also increased, and the water wash resistance and the high temperature resistance are also increased, which also proves that the fluorine contained in the adhesive of the present invention is contained. The atomic energy is homogenously compatible with the fluorine atom of the PTFE membrane, so that the aqueous PU adhesive which cannot be combined with the low surface energy PTFE film achieves the handling convenience, the washing resistance and the high temperature resistance due to the addition of the fluoride. (by 75 times of high temperature water wash test) and high strength and other properties.

The invention may be embodied in other specific forms without departing from the spirit and scope of the invention. The presently described embodiments are to be considered in all respects as illustrative and not restrictive. Within the scope.

1. . . PET cloth layer

2. . . PTFE layer

3. . . PET mesh layer

4. . . Coating composition of the present invention

Fig. 1 is a cross-sectional view showing a specific example of a layered body of the present invention.

Figure 2 is a block flow diagram illustrating the fabrication of a layer having a fluorine-containing substrate.

1. . . PET cloth layer

2. . . PTFE layer

3. . . PET mesh layer

4. . . Coating composition of the present invention

Claims (26)

A coating composition comprising the following components: 0.001 to 99.998 wt% of an aqueous PU; 0.001 to 10 wt% of a bridging agent; and 0.001 to 5 wt% of a tackifier; wherein the aqueous PU is derived from fluoride, It is obtained by reacting an isocyanate with a polyol of a polyester or a polyether. The coating composition of claim 1, wherein the coating composition has a viscosity of from about 5,000 to about 8,000 cp. The coating composition of claim 1, wherein the fluoride comprises a fluorine-containing glycol. The coating composition of claim 1, wherein the bridging agent comprises a bridging agent containing an NCO functional group. The coating composition of claim 1, wherein the tackifier comprises an aqueous nonionic tackifier. An adhesive, wherein the adhesive comprises a coating composition as in claim 1 of the patent application. A layer comprising a fluorine-containing substrate layer coated with the composition of claim 1 of the patent application. The layer of claim 7, wherein the material of the fluorine-containing substrate is PTFE. The layer of claim 7, further comprising one or more layers of material, wherein the material is selected from the group consisting of polyester, PP, PTFE, PE, PET, and combinations thereof. A layer as claimed in claim 9 wherein the layer of material is in the form of a woven or non-woven fabric. A layer as claimed in claim 9 wherein the layer of material is a microporous or non-porous film. A method for producing a layer comprising the steps of: (1) coating a coating composition of claim 1 on a first substrate; (2) pre-drying the first substrate; 3) laminating the surface of the coating composition of the first substrate coated with the first application of the first application with the fluorine-containing substrate to form a layer; (4) heating the layer, and And then cooling; (5) applying the coating composition of the first application of the patent application to the fluorine-containing substrate of the layer; (6) pre-drying the layer; (7) layering the layer The fluorine-containing substrate of the object is bonded to the second substrate; and (8) heating the layer having the first and second substrates, and then cooling. The method of claim 12, wherein the material of the fluorine-containing substrate is PTFE. The method of claim 12, wherein the material of the first or second substrate is polyester, PP, PTFE, PE or PET. The method of claim 12, wherein the material of the first or second substrate is a microporous or non-porous film. The method of claim 12, wherein the first or second substrate is in a woven or non-woven form. The method of claim 12, wherein the first or second substrate is in the form of a plain weave, a knit or a tricot. The method of claim 12, wherein the first or second substrate is PET tricot. The method of any one of claims 12 to 18, wherein the coating composition in the step (1) or the step (5) has a coating thickness of 0.01 to 0.05 mm. The method of any one of claims 12 to 18, wherein the coating method of the composition in the step (1) or the step (5) comprises knife coating and spot coating. The method of any one of claims 12 to 18, wherein the pre-drying temperature of the steps (2) and (6) is 70 to 90 °C. The method of any one of claims 12 and 18, wherein the heating conditions of the steps (4) and (8) are heating at 100 to 140 ° C for 0.5 to 3 minutes. The method of any one of claims 12 to 18, wherein the first or second substrate is subjected to a pressure-absorbing treatment by a water repellent. The method of claim 23, wherein the water repellent comprises a fluorine-containing water repellent. The method of claim 23, wherein the pressure suction treatment is performed at a normal temperature. For example, in the method of claim 23, drying and high temperature bridging are carried out after the pressure suction treatment.